GAS BURNER DEVICE AND METHOD FOR OPERATING A GAS BURNER DEVICE

Description

[0001] The invention relates to a gas burner device according to the preamble of claim 1 and a method for operating such a gas burner device according to the preamble of claim 9.

[0002] A gas burner device of the type mentioned above is known from patent document US 2010 / 218501 A1.

[0003] Another gas burner device is known from patent document WO 1993 / 18342 A1. This gas burner device consists of a flame body having a perforated burner surface section for the combustion of a gas-air mixture, each perforation having a porosity and the burner surface section having a porosity resulting from the area ratio of the total area of ​​the perforations to the area of ​​the burner surface section. Here and in the following, "flame body" is understood to mean any three-dimensional body suitable for arranging a burner surface section on it.The term "burner surface section" here and in the following means that either a single such section or several such sections can be provided on the flame body. In the case of multiple sections, which may differ particularly in their porosity, they can also merge seamlessly into one another. The gas used in this solution is, as the person skilled in the art will readily recognize, natural gas or methane. A "hole" here and in the following refers to a recess in the burner surface section, which may be circular, but need not be. It can also be designed, for example, as a slot or a cross-shaped slot (compare Figures 4 to 7 in the aforementioned document).

[0004] The invention is based on the objective of improving a gas burner device of the type mentioned above. In particular, a gas burner device that can also be operated with hydrogen is to be created.

[0005] This problem is solved with a gas burner device of the type mentioned at the outset by the features listed in the characterizing portion of claim 1.

[0006] According to the invention, the porosity of the burner surface section is greater than 35% (see page 1, line 27 of the aforementioned prior art), the thermal surface load resulting from the operation of the gas burner device is greater than 10,000 kW / m², and the round holes have a diameter of 0.4 to 0.8 mm. In other words, the invention provides for the use of a burner surface section with a porosity of more than 35% and a gas containing at least some hydrogen, and the operation of the gas burner device with a thermal surface load of more than 10,000 kW / m².

[0007] In other words, the solution according to the invention is characterized by the fact that, due to a comparatively high porosity of the burner surface section, a relatively large amount of the gas-air mixture can flow through the holes. An upper limit of the porosity is preferably 60%. This results, on the one hand, in good cooling of the burner surface section and thus effectively prevents flame flashback. On the other hand, due to the comparatively high porosity, a comparatively high thermal surface load can be achieved, which in turn enables a compact design of the gas burner device according to the invention. "Thermal surface load" refers to the heat output per unit area emitted by the burner surface section. An upper limit of the surface load is preferably 30,000 kW / m².

[0008] Other advantageous embodiments of the gas burner device and the method for operating such a gas burner device according to the invention are set out in the dependent claims.

[0009] For the sake of completeness, reference is also made to patent document WO 2020 / 079445 A1. While this document discloses a gas burner device for the combustion of hydrogen-containing gas, it does not provide information on porosity or surface loading, nor does it offer any suggestions to those skilled in the art for determining these parameters, which are important for good combustion.

[0010] Reference is also made to patent document US 3,936,003 A. This document discloses a gas burner device whose burner surface, however, only has a porosity in the range of 15% to 30%.

[0011] Furthermore, reference is made to patent document US 6,410,878 B1. This document discloses a gas burner device with a "flame support element" (orig.: flame support element), the latter having a volume porosity of over 35%, but not forming a porosity of a surface, in particular the burner surface, as defined in the present invention.

[0012] The gas burner device according to the invention or the method according to the invention for operating such a gas burner device, including its or its advantageous further developments according to the dependent claims, is explained in more detail below with reference to the graphic representation of a preferred embodiment.

[0013] It shows a schematic representation and is not to scale. Figure 1 shows a perspective view of an embodiment of the gas burner device according to the invention; Figure 2 shows a top view of a section of the burner surface with circular holes; and Figure 3 shows a section through the burner surface with a circular hole.

[0014] The gas burner device shown in the figures, which is particularly preferably designed as a fully premixed burner, initially consists, in a known manner, of a flame body 1 having a burner surface section 2 provided with holes 2.1. For the operation of this gas burner device, a gas-air mixture is combusted on the burner surface section 2, which, as mentioned, is arranged on a flame body 1. Furthermore, each hole 2.1 has a porosity area, and the burner surface section 2 has a porosity resulting from the ratio of the total area of ​​the holes to the area of ​​the burner surface section 2. The burner surface section 2 is preferably completely provided with regularly distributed holes 2.1.

[0015] Furthermore, it is preferably provided that the gas burner device has a modulation capability of 1:5, i.e. it can operate without problems in the range between 20 and 100% of its power.

[0016] Essential for the gas burner device according to the invention is that the porosity of the burner surface section 2 is more than 35%, that a thermal surface load resulting during operation of the gas burner device is more than 10,000 kW / m², and that the round holes 2.1 have a diameter D of 0.4 to 0.8 mm.

[0017] In procedural terms, it is therefore intended that a burner surface section 2 with a porosity of more than 35% and a gas containing at least a proportion of hydrogen are used and that the gas burner device is operated with a thermal surface load of more than 10,000 kW / m².

[0018] With regard to porosity, it is particularly preferred that it be less than 60%, preferably between 40% and 50%.

[0019] Regarding the gas, it is further preferably provided that it contains at least 25%, preferably at least 50%, particularly preferably at least 75%, and most preferably more than 90% hydrogen. The remaining proportion preferably consists of natural gas or the like.

[0020] As especially from Figure 2 It is evident that it is further preferably provided that at least some, preferably all, of the holes 2.1 are round, in particular circular.

[0021] Furthermore, it is preferably provided that the ratio "t / D" of the distance t between two hole centers to the diameter D of a hole 2.1 is between 1.125 and 2.25, preferably between 1.125 and 1.6, and particularly preferably between 1.2 and 1.4. It is also preferably provided that the edges of two holes 2.1 have a distance b (also called web width) of 0.1 to 0.5 mm from each other. More precisely, b denotes the smallest existing distance between the edges of two adjacent holes. It should be noted that, in the present invention, for a given hole geometry and arrangement, only pairs of values ​​b and D are used which, as described above, result in a porosity of more than 35% in order to ensure effective operation of the gas burner device.

[0022] Regarding the arrangement of the holes 2.1 on the burner surface section 2, it is particularly preferred that these may be optionally (as in Figure 2shown) are arranged on imaginary corners of, in particular, equilateral triangles or (not shown separately) on imaginary corners of rectangles, in particular squares (in the case of non-square rectangles there are then accordingly two b-values ​​perpendicular to each other).

[0023] Furthermore, as in Figure 1 As shown, and particularly preferably provided, the flame body 1 is designed as a cylinder and the burner surface section 2 with its holes 2.1 is arranged on an end face of the cylinder. As can be seen and as already explained at the outset, the burner surface section 2 does not have to fill or constitute the entire surface of the flame body 1, but can, for example, be designed as an annular area (relatively small in relation to the rest of the surface), as shown.

[0024] Regarding the material used, it is further preferably provided that the burner surface section 2 is optionally made of a metallic or ceramic material. The material of the burner surface section 2 particularly preferably has a thermal conductivity of 1 to 25 W / (m*K).

[0025] If a metallic material is used for the burner surface section 2, it is preferably provided that this material has a thickness s, see Figure 3 , from 1 to 3 mm.

[0026] If a ceramic material is used for the burner surface section 2, it is preferably provided that this material has a material thickness s of 8 to 12 mm, preferably 10 mm. Reference symbol list

[0027] 1 Flame body 2 Burner surface section 2.1 Hole bDistance DDiameter sMaterial thickness tDistance between two hole centers

Claims

1. A gas burner device, comprising a flame body (1) which has a burner surface section (2) provided with holes (2.1) for the combustion of a gas-air mixture, wherein each hole (2.1) has a hole area and the burner surface section (2) has a porosity resulting from an area ratio of a total sum of the hole areas and the area of the burner surface section (2), wherein the gas is formed containing at least a proportion of hydrogen, wherein at least some holes (2.1) are formed round, characterised in that the porosity of the burner surface section (2) amounts to more than 35%, that a thermal area load resulting during the operation of the gas burner device amounts to more than 10,000 kW / m2 and that the round holes (2.1) have a diameter (D) of 0.4 to 0.8 mm.

2. The gas burner device according to claim 1, characterised in that all the holes (2.1) are formed round.

3. The gas burner device according to claim 2, characterised in that a ratio of a distance between two hole centres (t) to the diameter (D) of a hole (2.1) amounts to between 1.125 and 2.25.

4. The gas burner device according to any one of claims 1 to 3, characterised in that edges of two holes (2.1) have a distance (b) of 0.1 to 0.5 mm from one another.

5. The gas burner device according to any one of claims 1 to 4, characterised in that the holes (2.1) are arranged on imaginary corners of triangles.

6. The gas burner device according to any one of claims 1 to 5, characterised in that that the flame body (1) is designed as a cylinder and that the burner surface section (2) with its holes (2.1) is arranged at an end face of the cylinder.

7. The gas burner device according to any one of claims 1 to 6, characterised in that the burner surface section (2) is optionally made of a metallic or ceramic material.

8. The gas burner device according to claim 7, characterised in that, a metallic material of the burner surface section (2) has a material thickness (s) of 1 to 3 mm.

9. A method for operating a gas burner device according to any one of claims 1 to 8, in which a gas-air mixture undergoes combustion at a burner surface section (2) which is arranged on a flame body (1) and provided with holes (2.1), wherein each hole (2.1) has a hole area and the burner surface section (2) has a porosity resulting from an area ratio of a total sum of the hole areas and the area of the burner surface section (2), wherein a burner surface section (2) with a porosity of more than 35% and a gas containing at least a proportion of hydrogen is used and the gas burner device is operated with a thermal area load of more than 10,000 kW / m2.